Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!mash
From: mash@mips.com (John Mashey)
Newsgroups: comp.arch
Subject: Re: Optimising C compiler question
Message-ID: <2418@spim.mips.COM>
Date: 18 Apr 91 04:11:05 GMT
References: <1991Apr8.193155.3911@vax5.cit.cornell.edu>
Sender: news@mips.COM
Distribution: comp
Organization: MIPS Computer Systems, Inc.
Lines: 15
Nntp-Posting-Host: winchester.mips.com

In article <1991Apr8.193155.3911@vax5.cit.cornell.edu> umh@vax5.cit.cornell.edu writes:
>Something I wonder about.
>C has provision for register variables, which are supposed to run faster than
>standard variables. How come one never sees register variables in any code?
>Are modern RISC compilers sufficiently good that they automatically make
>sensible choice of register variables?
Yes.  There are plenty of compilers around, at least {HP PA, MIPS, SPARC,
IBM, but I'm sure others} which pretty much ignore whether or not you
declare something register or not, and move variables in and out of
registers (not necesarily the same ones) as makes sense.
-- 
-john mashey	DISCLAIMER: <generic disclaimer, I speak for me only, etc>
UUCP: 	 mash@mips.com OR {ames,decwrl,prls,pyramid}!mips!mash 
DDD:  	408-524-7015, 524-8253 or (main number) 408-720-1700
USPS: 	MIPS Computer Systems MS 1/05, 930 E. Arques, Sunnyvale, CA 94086